The day will be a bank holiday in the UK.
Queen Elizabeth II's funeral will be held on Monday (19 September) at Westminster Abbey in London, Buckingham Palace has confirmed.
In a statement, the Palace also confirmed that Queen Elizabeth II will lie-in-state in Westminster Hall for four days.
The Palace said: "The State Funeral of Her Majesty The Queen will take place at Westminster Abbey on Monday 19 September.
"Prior to the State Funeral, The Queen will Lie-in-State in Westminster Hall for four days, to allow the public to pay their respects."
Princess Anne will accompany Queen Elizabeth II's body to London ahead of the funeral, Buckingham Palace says.
The monarch died peacefully on Thursday (8 September) at Balmoral Castle in Scotland.
Buckingham Palace said the coffin would depart for Edinburgh airport on Tuesday and then be flown to London by RAF Northolt, with the Queen's only daughter on board.
The coffin is expected to arrive at Buckingham Palace at 8pm on Tuesday, where King Charles III and Queen Camilla will witness its arrival.
https://twitter.com/RoyalFamily/status/1568631258657312770
The Queen will lay in state for four days before her funeral on 19 September.
She will be taken from Buckingham Palace to Westminster Hall on Wednesday, where the coffin will be rested on a raised platform, known as a catafalque.
Her coffin will be draped in the Royal Standard flag and once in Westminster Hall it will be topped with the Imperial State Crown, orb and sceptre.
Members of the public will then be able to file past and pay their respects.
The grand hall is the oldest part of the Palace of Westminster, at the heart of the British government.
The last member of the Royal Family to lie in state in the hall was the Queen Mother in 2002, when more than 200,000 people queued to view her coffin.
Earlier on Saturday, King Charles III announced that the day of the funeral would be a bank holiday.
